To meet the demand for wireless data traffic having increased since deployment of 4G (4th-Generation) communication systems, efforts have been made to develop an improved 5G (5th-Generation) or pre-5G communication system. Therefore, the 5G or pre-5G communication system is also called a ‘Beyond 4G Network’ or a ‘Post LTE System’. The 5G communication system is considered to be implemented in higher frequency (mmWave) bands, e.g., 60 GHz bands, so as to accomplish higher data rates. To decrease propagation loss of the radio waves and increase the transmission distance, the beamforming, massive multiple-input multiple-output (MIMO), Full Dimensional MIMO (FD-MIMO), array antenna, an analog beam forming, large scale antenna techniques are discussed in 5G communication systems. In addition, in 5G communication systems, development for system network improvement is under way based on advanced small cells, cloud Radio Access Networks (RANs), ultra-dense networks, device-to-device (D2D) communication, wireless backhaul, moving network, cooperative communication, Coordinated Multi-Points (CoMP), reception-end interference cancellation and the like. In the 5G system, Hybrid FSK and QAM Modulation (FQAM) and sliding window superposition coding (SWSC) as an advanced coding modulation (ACM), and filter bank multi carrier (FBMC), non-orthogonal multiple access (NOMA), and sparse code multiple access (SCMA) as an advanced access technology have been developed.
The Internet, which is a human centered connectivity network where humans generate and consume information, is now evolving to the Internet of Things (IoT) where distributed entities, such as things, exchange and process information without human intervention. The Internet of Everything (IoE), which is a combination of the IoT technology and the Big Data processing technology through connection with a cloud server, has emerged. As technology elements, such as “sensing technology”, “wired/wireless communication and network infrastructure”, “service interface technology”, and “Security technology” have been demanded for IoT implementation, a sensor network, a Machine-to-Machine (M2M) communication, Machine Type Communication (MTC), and so forth have been recently researched. Such an IoT environment may provide intelligent Internet technology services that create a new value to human life by collecting and analyzing data generated among connected things. IoT may be applied to a variety of fields including smart home, smart building, smart city, smart car or connected cars, smart grid, health care, smart appliances and advanced medical services through convergence and combination between existing Information Technology (IT) and various industrial applications.
In line with this, various attempts have been made to apply 5G communication systems to IoT networks. For example, technologies such as a sensor network, Machine Type Communication (MTC), and Machine-to-Machine (M2M) communication may be implemented by beamforming, MIMO, and array antennas. Application of a cloud Radio Access Network (RAN) as the above-described Big Data processing technology may also be considered to be as an example of convergence between the 5G technology and the IoT technology.
As the use and functionality of wearable devices continues to grow, users carry more and more handsets. Wearable devices are mostly equipped with short-range communication chips, such as Wi-Fi and Bluetooth modules. Accordingly, a wearable device may communicate with only terminals that are positioned within a short range, e.g., Bluetooth/Bluetooth Low Energy (BLE), or may cover a spot, e.g., Wi-Fi, not the nationwide service that would be covered with cellular communication. The user carrying multiple devices respectively having different communication chips independently use each device.
With a device only with short-range communication chips, the user may use additional services only when a plurality of terminals are positioned in the service coverage area. For example, when the user is wearing a smartwatch equipped with a Bluetooth chip, if a smartphone and the smartwatch are located in the service area, the smartwatch may receive, through Bluetooth, voice calls delivered from the communication network to the smartphone. However, the smartwatch, departing from the service area, cannot communicate with the smartphone through Bluetooth, and voice call communication using the smartwatch is unavailable. In other words, if the user wearing the smartwatch leaves behind the smartphone, it is impossible for the user to use nationwide voice call communication with his smartwatch.
To address such issue, the wearable device may have a chip for cellular communication. If so, however, a universal subscriber identity module (USIM) chip should also come along. As per the standards of the 3rd Generation Partnership Project (3GPP) managing USIM-related standards, the USIM chip has the International Mobile Subscriber Identity (IMSI), indicating the user's ID, and the user's phone number, Mobile Station International ISDN Number (MSISDN) mapped one-to-one. In other words, each device carried by the user has its own phone number. For instance, a smartphone has phone number 1, and a wearable device has phone number 2. Thus, the user ends up having as many phone numbers as the number of devices he owns. Under such environment, the user should use two independent phone numbers in order to receive voice calls. The opposite party should call the user at phone number 1 to allow the user to receive voice calls through the smartphone and at number 2 through the smartwatch. For example, one user needs to use two phone numbers to receive voice calls through wireless communication, and this is quite bothering.
Another approach to enable communication of voice calls using multiple terminals is to use the call forwarding service that is an additional service that is offered from the mobile service provider. However, call forwarding services of the related art may be executed only when the devices are positioned in the shadow area, the phones stay turned-off, no response, or when a call-related event occurs that may be discovered by the network, but not when the devices' own issues arise, e.g., when the devices go away from each other.
Further, the user may desire to communicate voice calls with other devices, not the smartphone. For example, when the user is using his smartphone for purposes other than calling or call receiving, such as running a certain application on the phone, image capturing or filming using the phone, the user may want voice calls to be received by not his phone but the smartwatch. The call forwarding service of the related art serviced by the mobile service provider cannot respond to such issue.
Therefore, a need exists for a method and an apparatus for enabling a plurality of terminals each equipped with a cellular communication chip to communicate voice calls using the same phone number.
The above information is presented as background information only to assist with an understanding of the present disclosure. No determination has been made, and no assertion is made, as to whether any of the above might be applicable as prior art with regard to the present disclosure.